Literally and figuratively…

So I’ve got a set of Oro Biancos that I decided to upgrade with Jagwire HyFlow hoses. The brakes are now just not bleeding properly – no matter how closely I follow the official Formula bleed process I always end up with air in the hoses and squishy levers. A shop mechanic has tried them several times and I’ve tried 5 or 6. No matter what we do air always appears from somewhere and fluid is disappearing in to them like they’re 2 mini black holes – no sign of leaks anywhere.

They’ve previously been bled when I shortened the OEM hoses and that all went swimmingly.

Did a bit of research and there’s a thread on MTBR about the Jagwire hoses but that problem was supposedly solved by an upgrade to better/stiffer liner material; the hoses I have are this newer version.

Anybody any ideas or handy hints…?

You need me Nut and his giver!

Have you put the tiny o rings under the bleed screw? If you have then I’ve no idea, when I put goodrich hoses on mine I used these instructions and they were perfect, I made a jig out of some old bars and a quill stem
http://formulabrakeusa.com/formula/wp-content/uploads/2009/11/bleed_instructions_final.pdf

Between our hire bikes and my Mrs’ bike, we’ve got a few different varieties of formula brake. The bleeding instructions for each brake are very similar but NOT quite the same. The differences are very minor, but crucial. Usually to do with how/when you pull/release the brake lever during the bleed process.

Might be worth checking that you’re precisely following the instructions for the exact set of brakes you have. We found, for example, that there are crucial differences between bleeding the R1 and RX.

Folks, thanks for the reples – Mr Nutt’s thread is awesome!

Khani, yep, got the o-rings under the bleed screws. Stevo, yep, checked the instructions to make sure – got them direct from the Formula site, no matter which model of Oro, the instructions are the same.

Like I say, bled the brakes before with the OEM hoses and no issues, it appears to be the change to the HyFlow hoses that’s caused the problem. Will give Dave and Stephanie a go later anyway though…

Regardless of whether you’ve got the o-rings fitted, if you pull on the syringe too hard, you’ll get air blurbling through from under the o-rings. It requires a bit of feel for when you’ve got the air out, rather than yanking away at it wondering why the bubbles won’t stop.

That said, I’ve only used OEM hoses. I’ve often found it easier to steadily cycle the fluid through from one syringe to the other tapping at stuff in between gentle tugs on the syringe plunger.

Mine are oro bianco’s, the destructions I linked to worked perfectly when I fitted longer goodrich hoses, mine wouldn’t bleed when fitted to the bike though, I had to use the jig to do it right.

Khani, those are the exact same instructions I used, and took brakes off bike, put them on a homemade handlebar jig too.

if you pull on the syringe too hard, you’ll get air blurbling through from under the o-rings

I “may” have been a little over-energetic in my desire to rescue every single tiny bubble from a deep, dark, DOT fluid grave…